A 21-year-old model from Belfast, Northern Ireland, died on the evening of 15 October just 10 months after losing her mom to bowel cancer.

Mairead O'Neill had graduated from university in August and according to friends had the world at her feet and a promising career as a model, Fox News reports.

The young woman died just hours after sharing Instagram videos and snaps of herself out on the town with friends at a Belfast pub called Pug Uglys, The Sun writes.

While the cause of death is unknown, a Northern Ireland Police Service spokesman has said, "Police attended the scene of a sudden death of a woman in the south Belfast area on Monday October 15. The death is not being treated as suspicious."

The model was still grieving the death of her mother and shared posts in which she expressed her heartbreak, Belfast Live reports.

Cathy Martin, the model agency boss who worked with Mairead for six years, said that it was a shock to hear of the young model's passing.

"We don't know exactly what happened but she'd been having a very difficult time following the death of her mum from bowel cancer," Martin said.

"She had a lot of support but her heart was broken. It's so sad to think that she's gone now too."

Cathy then went on to say that Mairead was a clever, grounded and smart young lady who was doing well with her modelling and worked hard.